POLYETHYLENE FOR SILANE-CROSSLINKED PIPE, SILANE-MODIFIED POLYETHYLENE COMPOSITION, AND SILANE-CROSSLINKED PIPE, AND METHOD FOR PRODUCING THE PIPE

摘要

PROBLEM TO BE SOLVED: To provide a polyethylene for silane-crosslinked pipes, excellent in durability, appearance and extrusion moldability, and suitable for (hot) water feed pipes, to provide a composition containing the same, to provide a silane-modified polyethylene composition, to provide such a silane-crosslinked pipe, and to provide a method for producing the silane-crosslinked pipe.;SOLUTION: The polyethylene for silane-crosslinked pipes is provided, meeting the following requirements: (a1) consisting of a copolymer of ethylene and a 3-20C α-olefin; (a2) the density is 935-960 kg/m³; (a3) the melt flow rate at 190°C under a load of 2.16 kg is 0.1-10 g/10 min; (a4) the Mw/Mn is 3.5-5.5 as determined by gel permeation chromatography (thereafter, referred to as GPC); (a5) the number of the short chains: n (n/1,000C) is 3-25 when logMw is 3.5-5.5, as determined in combination of GPC with FT-IR; and (a6) the differential expression and integral expression of the dissolution-temperature curve for the total polyethylene elution level, as determined using a cross fractionator as a combination of the elution fractionation with temperature rise with GPC, meet a specific condition(s).;COPYRIGHT: (C)2011,JPO&INPIT